Statistical analyzer of working process parameters of machinery

ABSTRACT

The proposed statistical analyzer comprises a converter of physical quantities to voltage, connected to direct inputs of comparators whose number corresponds to that of voltage quantization levels. The analyzer also includes adders. One input of each adder is connected to the output of a standard voltage generator; the output of each adder is connected to the inverting input of a comparator. The output of each comparator is connected to the second input of each adder corresponding to a quantization level which is one level below the quantization level corresponding to this comparator. The statistical analyzer of this invention is marked by a high accuracy and reliability and makes it possible to obtain a bar chart of any working process parameter of a machine.

The present invention relates to monitoring and measuring devicesintended for statistical analysis of electric signals and, moreparticularly, to a statistical analyzer of working process parameters ofmachinery.

The statistical analyzer of this invention is applicable, in the main,to monitoring working process parameters of mining machines, as well asof different electrical and mechanical equipment.

The monitoring of working process parameters ensures a high efficiencyof machinery and equipment. The working processes of mining,construction, road-building and agricultural machinery, as well astransport vehicles, which are subjected to the effects of great dynamicloads, are of a markedly random and unstable nature. Actual values ofworking process parameters of machinery, such as power, moment, force,pressure, speed, temperature, and current, can be converted to randomelectric signals by means of converters of physical quantities. Hence,working process parameters of machinery can be monitored bystatistically analyzing electric signals.

The existing monitoring and measuring equipment does not make itpossible to monitor parameters of machines' working processes duringoperation, or throughout the life of a machine, or at least some part ofits service life.

The sphere of application of the known statistical analyzers of workingprocess parameters of machinery is limited by their low reliability andaccuracy.

There is known a statistical distribution analyzer which comprises a setof contacts mounted on a level recorder, and a unit containing a pulseoscillator and thirteen electromechanical counters, of which twelve areused to register level distribution (cf. The Products Catalog of theDanish firm Bruel and Kier). As voltage is applied to the input of therecorder, the pulse oscillator sends its pulses via one of the contactsto the counter which registers the duration of a signal at a givenlevel. Displays of the counters are indicative of the distribution ofthe electric signal being monitored.

The analyzer under review does not make it possible to analyze signalsat a frequency of more than 1 to 2 Hz and has a limited memory capacity,designed for a maximum of 24 hours of continuous operation. As a result,the analyzer cannot be used for analyzing signals over a prolongedperiod of time, for example, a week, a month or a year. The analyzermust be complete with a level recorder; it has a big size and lowreliability due to the presence of mechanical contacts. These factors donot allow on site application of the analyzer.

There is also known a statistical analyzer of working process parametersof machinery, comprising a converter of physical quantities, whichcharacterize the operating conditions of machinery, into voltage. To theoutput of said converter there are connected the direct inputs of ncomparators whose number is equal to that of voltage quantizationlevels. The output of each of said comparators is connected to thecontrol input of a respective switch. The second input of eachcomparator is connected to the output of a stabilized pulse currentgenerator. The output of each comparator is connected to a respectiverecorder. The inverting input of each comparator is electrically coupledto a respective output of a standard voltage generator (cf. USSRInventor's Certificate No. 436,371, Cl. G607 c).

The latter statistical analyzer further includes diodes, the plate ofeach of said diodes being connected to the inverting input, whereas thecathode of each of said diodes is connected to the output of the switchof a given quantization level and to the inverting input of thecomparator of the next lower level. The recorders are electrochemicalmercury integrators.

The analyzer in question has no more than three quantization levels; itsadjustment is extremely complicated, whereas the accuracy andreliability are low.

It is an object of the present invention to provide a statisticalanalyzer of working process parameters of machinery, featuring improvedaccuracy and reliability.

The foregoing object is attained by providing a statistical analyzer ofworking process parameters of machinery, comprising a converter ofphysical quantities, which characterize the operating conditions ofmachinery, into voltage, to whose output there are connected directinputs of a plurality of n comparators, the number of said comparatorsbeing equal to that of voltage quantization levels, the output of eachof said comparators being connected to the control input of a respectiveswitch, the second input of each of said switches being connected to theoutput of a stabilized pulse current generator, the output of each ofsaid switches being connected to a respective recorder, whereas theinverting input of each of said comparators is electrically coupled to arespective output of a standard voltage generator, which statisticalanalyzer includes, according to the invention, (n - 1) adders, one inputof each of said adders being connected to a respective output of thestandard voltage generator, the output of each of said adders beingconnected to the inverting inputs of comparators corresponding to thequantization levels from the lowest to the highest but one, the outputof each comparator being connected to the second input of each addercorresponding to a quantization level which is one level below thequantization level corresponding to this comparator.

The proposed statistical analyzer is marked by a high accuracy andreliability and is easy to adjust.

Other objects and advantages of the present invention will be morereadily understood from the following detailed description of apreferred embodiment thereof to be read in conjunction with theaccompanying drawing which is a block diagram of a statistical analyzerof working process parameters of machinery, in accordance with theinvention.

Referring to the drawing the proposed statistical analyzer of workingprocess parameters of machinery comprises a converter 1 of physicalquantities to voltage. The physical quantities, which characterize theoperating conditions of machinery, may include, for example, the powerinput of a motor, the torque of a transmission, axial and radial forcesapplied to a machine's actuator, the pressure in a drive's hydraulicsystem, the temperature of electromotor windings, and motion of amachine.

Connected to an output 2 of the converter 1 are direct inputs 3₀, 3₁, 3₂and 3₃ of n comparators 4₀, 4₁, 4₂ and 4₃ whose number corresponds tothat of voltage quantization levels.

The outputs 5₀, 5₁, 5₂ and 5₃ of each comparator 4₀, 4₁, 4₂ and 4₃ areconnected to a control input 6₀, 6₁, 6₂ and 6₃ of a respective switch7₀, 7₁, 7₂ and 7₃ to whose second input 8₀, 8₁, 8₂ and 8₃ there isconnected an output 9 of a stabilized pulse current generator 10. Anoutput 11₀, 11₁, 11₂ and 11₃ of each switch 7₀, 7₁, 7₂ and 7₃ isconnected to a respective recorder 12₀, 12₁, 12₂ and 12₃. In theembodiment under review, the recorders 12 are electrochemical mercuryintegrators (cf. the products catalogue of Takelec Airtronic of 1972).The function of a recorder 12 can also be performed by anelectromechanical counter.

In the embodiment under review, the comparator 4 is built around anoperational amplifier. The switch 7 is a microcircuit transistor switch(cf. The Handbook of Semiconductor Electronics, ed. by Lloyd P. Hunter).An inverting input 13₀, 13₁, 13₂ and 13₃ of the comparator 4₀, 4₁, 4₂and 4₃ corresponding to the highest quantization level is electronicallycoupled to an output 14 of a standard voltage generator 15.

The statistical analyzer futher includes (n - 1) adders 16₁, 16₂ and16₃. One input 17₁, 17₂ and 17₃ of each adder 16₁, 16₂ and 16₃ isconnected to a respective output 18₁, 18₂ and 18₃ of the standardvoltage generator 15.

The standard voltage generator 15 applies voltage to the input 13₀, 13₁,13₂ and 13₃ of each comparator 4₀, 4₁, 4₂ and 4₃ via a correspondingadder 16₁, 16₂ and 16₃. The magnitude of this voltage corresponds to avoltage quantization level which corresponds to the respectivecomparator 4₀, 4₁, 4₂ and 4₃.

Outputs of the adders 16₁, 16₂ and 16₃ are connected to the inputs 13₁,13₂ and 13₃ of the comparators 4₁, 4₂ and 4₃ corresponding to thequantization levels from the lowest to the highest but one. The output5₁, 5₂ and 5₃ of each comparator 4₁, 4₂ and 4₃ is connected to anotherinput 19₁, 19₂ and 19₃ of each adder 16, which corresponds to aquantization level that is one level below the quantization levelcorresponding to this comparator 4₁, 4₂ and 4₃. Thus the number ofinputs 19₁, 19₂ and 19₃ of each adder 16₁, 16₂ and 16₃ increases as thequantization level goes down.

The statistical analyzer also includes a power source 20 connected tothe converter 1, the comparators 4₀, 4₁, 4₂ and 4₃, the stabilized pulsecurrent generator 10, the adders 16₁, 16₂ and 16₃, and the standardvoltage generator 15.

The proposed statistical analyzer of working process parameters ofmachinery operates as follows.

The converter 1 of physical quantities to voltage is a power converter.The voltage at the output of this converter corresponds to the actualpower intake of a machine's electromotor. In the embodiment underreview, there are four voltage quantization levels.

Consider a case when voltage at the output 2 of the power converter 1 isin excess of that of the first, or the lowest, quantization level and,consequently, in excess of the voltage across the direct input 3₀ of thecomparator 4₁. From the standard voltage generator 15, standard voltageis applied to the inverting input 13₁ of the comparator 4₁ via the adder16₁. As this takes place, at the output 5₁ of the comparator 4₀ there isproduced a signal which is applied to the input 6₀ of the firstquantization level switch 7₀. The switch 7₀ is driven into conduction,and current flows from the output 9 of the stabilized pulse currentgenerator 10 through the electrochemical mercury integrator 12₀. Thelatter's scale is graduated in hours, hence, the reading of theintegrator makes it possible to find, without any conversion, the timeduring which the machine's electromotor has worked at a power outputwithin the range between the first and second quantization levels.

As soon as the voltage at the output 2 of the power converter 1 is inexcess of that of the second quantization level, i.e. as soon as thevoltage at the direct input 3₁ of the comparator 4₁, corresponding tothe second quantization level, is in excess of the voltage at theinverting input 13₁ of said comparator 4₁, at the latter's output 5₁there is produced a signal which is applied to the input 6₁ of theswitch 7₁ corresponding to the second quantization level. The switch 7₁is driven into conduction, and current flows from the output 9 of thestabilized pulse current source 10 through the electrochemical mercuryintegrator 12₁. As this takes place, the integrator 12₁ registers thetime during which the machine's electromotor has worked at an inputpower within the range between the second and third quantization levels.Simultaneously, a signal from the output 5₁ of the comparator 4₁,corresponding to the second quantization level, is applied to one of theinputs 19₂ of the adder 16₂ corresponding to the third quantizationlevel. As a result, voltage at the output of the adder 16₂ and,consequently, voltage at the inverting input 13₂ of the comparator 4₂corresponding to the third quantization level becomes greater than thevoltage across the direct input 3₂ of the comparator 4₂. The signal atthe output 5₂ of the comparator 4₂ becomes zero, and the switch 7₂ isrendered non-conducting, so no current is passed to the electrochemicalmercury integrator 12₂ corresponding to the third quantization level.

Whenever voltage across the output 2 of the power converter 1 is inexcess of each next, higher, quantization level, current is passedthrough the electrochemical mercury integrator 12 corresponding to thisquantization level, but is not passed through the electrochemicalmercury integrator 12 corresponding to the previous, lower, quantizationlevel.

When voltage across the output 2 of the power converter 1 is in excessof the fourth, or the highest, quantization level, current is onlypassed through the electrochemical mercury integrator 12₃ correspondingto the fourth quantization level, and there is registered the timeduring which the machine's electromotor operates at a power output abovethe fourth and last quantization level.

If subsequently there is a drop in the voltage across the output 2 ofthe power converter 1, current is passed through the electrochemicalmercury integrator 12 corresponding to the given quantization level, butis not passed through the electrochemical mercury integrator 12corresponding to the previous, higher quantization level.

At each moment of time, current only flows through a singleelectrochemical mercury integrator 12 which registers the time duringwhich the machine's electromotor runs at a power output within the rangebetween the actual and the next, higher, quantization levels.

Thus the statistical analyzer of the present invention makes it possibleto determine power level distribution, or obtain an input power barchart of a machine's electromotor.

Bar charts of other working process parameters of machinery are obtainedthrough the use of an appropriate physical quantity-to-voltageconverter. The statistical analyzer of this invention is highlyaccurate, reliable and easy to adjust.

What is claimed is:
 1. A statistical analyzer of working processparameters of machinery, comprising:a converter of physical quantities,which characterize operating conditions of machinery, to voltage; aplurality of comparators, whose number is equal to that of voltagequantization levels, each having a direct input connected to the outputof said converter of physical quantities to voltage, and an output; aplurality of switches, each having a control input connected to theoutput of a respective comparator, and an output; a stabilized pulsecurrent generator having an output connected to a second input of arespective switch; a plurality of recorders connected to said outputs ofsaid respective switches; a plurality of adders corresponding to thevoltage quantization levels from the lowest to the highest but one, eachhaving an output connected to a respective comparator, and a group ofinputs; a standard voltage generator having a group of outputs connectedto a respective adder, and an output connected to that of saidcomparators which corresponds to the highest quantization level, and aninput; the output of each of said comparators being connected to saidinput of said group of inputs of a respective adder correspondong to aquantization level which is one level below the quantization levelcorresponding to this comparator; a power source connected to saidconverter of physical quantities to voltage, said comparators, saidstandard voltage generator and said adders.